UPDATE: 12:30 P.M.: Bruins coach Bruce Cassidy made it official Saturday ahead of Game 3. Defenseman Matt Grzelcyk is out tonight and John Moore is in.
Grzelcyk took a hard hit from Oskar Sundqvist in Game 2 and was placed in the NHL's concussion protocol. Sundqvist was suspended for Game 3 tonight by the NHL.
Cassidy suggested Friday that Moore could take Grzelcyk's place alongside Connor Clifton on Boston's third defensive pair, which is where the veteran defenseman skated Friday afternoon in St. Louis.
Moore has played sparingly of late, appearing in just five games in the Stanley Cup Playoffs, four of which came against the Toronto Maple Leafs in the first round. The 28-year-old hasn't registered a point in those contests and is a minus-4.
Cassidy had other options, as 20-year-old Finnish prospect Urho Vaakanainen joined the Bruins for Friday's skate. Steven Kampfer also could slot into the lineup, although he's a right-handed shot (unlike Moore and Vaakaneinen) and likely wouldn't pair with Clifton.
Karson Kuhlman was the other newcomer to the Bruins' Friday practice session, replacing Patrice Bergeron on the top line as the veteran center took a maintenance day. Bergeron was back on the ice for practice on Saturday.
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